New centraliser plates are available "from most good stockists" and it's not a fortune . now you have shimmed-up the quadrant, be careful, it may bind when you refit the cover.
norvin
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The cryptic comments about ears on centralising plates stem from the fact that you are now selecting five gears instead of four but only using the same amount of rotation on the cam plate. From this you can see that each positive stop action on the gear lever needs to result in less movement of the cam plate to avoid overselecting the gear. Many people do this by building up the 'ears' on the G49 stop plate and then filing them to get the required amount of movement.
When I did mine, several years ago, I made a round sleeve that pressed over the round boss between the ears. This has the same effect of reducing the selection travel. The outer end of the sleeve is chamfered internally and the boss peened over to retain it, along with a dollop of 'stud and bearing fit'. Don't ask me what the diameter of the sleeve is that was a bit of trial and error.
I am sure that there are a dozen clever reasons why this isn't the way to do it but my gear change has been great for the past 25,000 miles.
Peter
When I did mine, several years ago, I made a round sleeve that pressed over the round boss between the ears. This has the same effect of reducing the selection travel. The outer end of the sleeve is chamfered internally and the boss peened over to retain it, along with a dollop of 'stud and bearing fit'. Don't ask me what the diameter of the sleeve is that was a bit of trial and error.
I am sure that there are a dozen clever reasons why this isn't the way to do it but my gear change has been great for the past 25,000 miles.
Peter
Thanks for all your info.
I ordered a new G49 lever stop, G57 stop plate adjuster, G70 centralising spring, G71 helper spring from the club. As usual they arrived the next day.
The box is assembled and gear selection is great with no apparent over selection whilst the bike is on the bench.
Refitted the V3 clutch and got it out for it's MOT.
Damn, the clutch is slipping like mad.
Stripped the clutch and cleaned everything and put it back together,
It's still slipping so badly you can't kick it.
It appears that the splines on the mainshaft are about 1.5mm longer than on the original and the clutch centre is further on the shaft making the space larger between the clutch centre and the pressure plate.
It's hard to tell without dismantling the box completely to check the shaft lengths and details. The clutch centre is securely on and I'm loath to remove it but it appears the clutch needs another steel plate to take up the slack.
Have any unhappy readers had any similar experience whilst fitting a 5 speed box?
I ordered a new G49 lever stop, G57 stop plate adjuster, G70 centralising spring, G71 helper spring from the club. As usual they arrived the next day.
The box is assembled and gear selection is great with no apparent over selection whilst the bike is on the bench.
Refitted the V3 clutch and got it out for it's MOT.
Damn, the clutch is slipping like mad.
Stripped the clutch and cleaned everything and put it back together,
It's still slipping so badly you can't kick it.
It appears that the splines on the mainshaft are about 1.5mm longer than on the original and the clutch centre is further on the shaft making the space larger between the clutch centre and the pressure plate.
It's hard to tell without dismantling the box completely to check the shaft lengths and details. The clutch centre is securely on and I'm loath to remove it but it appears the clutch needs another steel plate to take up the slack.
Have any unhappy readers had any similar experience whilst fitting a 5 speed box?
I fitted a newby clutch and belt drive
I had to reduce the clutch securing nut to clear the clutch spring plate and I added an aluminium backing plate from 1/4" ally plate secured to spring plate with coutersunk screws and turned to match this gave enough clearance for the plates to secure home under spring pressure without hitting the reduced nut
Is this the reverse of your situation?
It would seem that fitting any clutch to a 5 speed is not straight forward-but its worth it
I had to reduce the clutch securing nut to clear the clutch spring plate and I added an aluminium backing plate from 1/4" ally plate secured to spring plate with coutersunk screws and turned to match this gave enough clearance for the plates to secure home under spring pressure without hitting the reduced nut
Is this the reverse of your situation?
It would seem that fitting any clutch to a 5 speed is not straight forward-but its worth it
My Norvin engine has had its lug cut off many moons ago (not by me) i am thinking of getting it welded back on, i know its been successfully done but can it be welded on without stripping the whole thing down? its been rebuilt in the past and has not done that many miles.
Well yes it can be welded back on without stripping, welding is the easy part. The engine will have to come out of the frame and after stripping the primary, the whole engine unit will have to be heated at least to a "hot" running temperature. Welding can then be done in short bursts so as to keep the temperature within reason. Now the reason why it can't all be done with out dismantling. The area adjacent to the weld will pull so the face of the primary cavity will have to be built up in that area. Then it will need to be machined back flush with the rest of the primary chain case face. Best it is dismantled to do some thing like this.
It´s very similar to George Brown´s idea with NERO! So, your idea is not at all wrong! Why not put footrests 2 inches in front of down tubes of your wideline frame, change gear on the right side without rearset leverage without tapping on your silencer, when changing gears? Drop this dreadful Norton rear brake into the bin and fit a nice standard drum brake with sprocket on one side and brake operation on the opposite, so having the complete brake mechanism on the left. This enables you to have a nice narrow foot position behind the clutch housing and a nice tank grip with your knees. No clip ons, just a standard VINCENT
straight handle bar, and you have a nice tourer, with a modern riding position. A very good rear brake is the one used in GT750 Ducatis. It was capable to block the rear wheel at any speed! It was quite popular, at that time and was used in several italian bikes. I have one of a Guzzi Falcone in my Norvin, which
is possibly the same. Dia. 200mm, and much cheaper than all these retro drum brakes of nowadays.
straight handle bar, and you have a nice tourer, with a modern riding position. A very good rear brake is the one used in GT750 Ducatis. It was capable to block the rear wheel at any speed! It was quite popular, at that time and was used in several italian bikes. I have one of a Guzzi Falcone in my Norvin, which
is possibly the same. Dia. 200mm, and much cheaper than all these retro drum brakes of nowadays.
Hello, Glenliman,
would you mind, giving us the timing figures you found with these cams? Would be interesting to compare. If I remember correctly, George and Cliff Brown used
curved cam followers first in NERO for which the cams looked quite rectangular in profile. Nothing new to PEI, either, as he writes in TFS about it.
I have pinned my "D" Shadow cams (original ones) on a graph with symmetrical overlap and with the standard, non-symmetrical overlap: There are astonishingly wide angles, where the symmetrical timing delivers wider open valves when wanted! The engine ran nicely with it, but, as I have no dynamometer, and did not want to torture my engine, until it doesn´t accelerate any more, I couldn´t find out, which timing is best.
My inlets are ported to 36mm, so that I can see the valves, when the throttle is wide open, but it isn´t of any use on country roads, when enjoying
your VINCENT... Perhaps Terry reads this and gives us some facts...
cheers,
would you mind, giving us the timing figures you found with these cams? Would be interesting to compare. If I remember correctly, George and Cliff Brown used
curved cam followers first in NERO for which the cams looked quite rectangular in profile. Nothing new to PEI, either, as he writes in TFS about it.
I have pinned my "D" Shadow cams (original ones) on a graph with symmetrical overlap and with the standard, non-symmetrical overlap: There are astonishingly wide angles, where the symmetrical timing delivers wider open valves when wanted! The engine ran nicely with it, but, as I have no dynamometer, and did not want to torture my engine, until it doesn´t accelerate any more, I couldn´t find out, which timing is best.
My inlets are ported to 36mm, so that I can see the valves, when the throttle is wide open, but it isn´t of any use on country roads, when enjoying
your VINCENT... Perhaps Terry reads this and gives us some facts...
cheers,
A beautiful bike on a nice picture, John!
Could you tell me, who made that kickstarter? I have the longer version of the std. CB750- Honda kickstart lever fitted, but it is still too short. I have my footrest abt 2in wider forward than you and the gearlever direct without setback leverage. This kind of footrest position doesn´t go together with the standard kickstartlever, anymore. I see, that you also have a mainstand fitted. can I have some more details about it? I had a modified MOTO GUZZI main stand fitted, but it was heavy and looked ugly, so it´s off again.
kind regards,
Could you tell me, who made that kickstarter? I have the longer version of the std. CB750- Honda kickstart lever fitted, but it is still too short. I have my footrest abt 2in wider forward than you and the gearlever direct without setback leverage. This kind of footrest position doesn´t go together with the standard kickstartlever, anymore. I see, that you also have a mainstand fitted. can I have some more details about it? I had a modified MOTO GUZZI main stand fitted, but it was heavy and looked ugly, so it´s off again.
kind regards,
I'll do some searching, I have the numbers somewhere. On port sizes, the thinking at one time was "If in doubt, Hog it out". I have one Rapide with two front heads, 34mm porting and carbs, lightning cams , 9 to one. It was set up that way back in the seventies for sprinting. It goes OK but my other Rapide has stock heads, Shadow sized stubs/carbs & 8 to one compression. The small port bike makes greater power all over the range, even at top.
Now it seems the tuners are more interested in port shape than adding size, in fact too large of an intake port slows the flow velocity which in turn reduces the density of charge and greatly reduces overall power. Sometimes the gain may be there, but only at very high RPM where the flow velocity is high enough to create the necessary density of charge. This can work OK for some race bikes, but even there midrange power is needed coming out of corners.
I've noticed the Norton Commando Daytona tuners are now seeking older small port donor heads in order to get the desired shape for racing without ending up with a port that is too large. The big port Combat Commando heads that were in demand at one time are considered ruined by modern standards. Also, polished ports are out, ground finish is the new way for better atomization and swirl.
Its tough to argue with these tuners when they have dyno charts and Daytona wins to back up their claims.
Glen
Now it seems the tuners are more interested in port shape than adding size, in fact too large of an intake port slows the flow velocity which in turn reduces the density of charge and greatly reduces overall power. Sometimes the gain may be there, but only at very high RPM where the flow velocity is high enough to create the necessary density of charge. This can work OK for some race bikes, but even there midrange power is needed coming out of corners.
I've noticed the Norton Commando Daytona tuners are now seeking older small port donor heads in order to get the desired shape for racing without ending up with a port that is too large. The big port Combat Commando heads that were in demand at one time are considered ruined by modern standards. Also, polished ports are out, ground finish is the new way for better atomization and swirl.
Its tough to argue with these tuners when they have dyno charts and Daytona wins to back up their claims.
Glen
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